IMO Morrowind and Skyrim aren't the greatest RPG's ever, though they rank up there, but I don't think any game has captured the immersion factor like those two. Just turn the lights out, turn the background music off, and walk around in that fantasy world and it feels like you're really there. At least to me. I don't think any game has ever made me feel like I was really there the way Morrowind and Skryrim did. (Oblivion.... um.. no, it seemed like those were almost comic book graphics or cartoonish or something... just didn't get the immersion with that one).

I don't know if you understand the term immersion correctly,
it's not about game's art it's about feeling like your in the game and this can be done even in cartoonish games.

Why do this ? Isn't the music there to actually help with the immersion ?

I understand immersion very well, and for me, it can't be done in cartoonish games, because it doesn't feel real. For some it can, that's fine. Not for me. I'm not saying graphics are all that makes immersion, but bad graphics can ruin immersion. At least for me. If not for you, then you and I just look at differently, that doesn't mean I don't understand what immersion means. I understand perfectly well what it means. Well, yeah, except for me when I'm out adventuring and only hearing the ambient sounds of the world around me, that just feels more real than if I'm hearing background music. But man I did love Morrowind's music. Actually liked that better than Skyrim's, but I thought Skyrim was a much more "alive" world to roam around in. But Morrowind is close, they're both just so cool, I can literally turn those games on and just wander around for a few minutes, and the next thing I know six hours have passed. And for all of those six hours it felt like I was actually in that world. Not all games capture that feeling, it's just IMO Morrowind and Skyrim did it better than any other I've ever played.

ADDED: Oh, and another Bethesda game, Fallout 3 also had a good immersion for me. Actually better than Fallout NV, although I thought the gameplay in Fallout NV was far superior.

On the other hand, i got pretty immersed in Oblivion too! When i first played it, it was winter in the real world and every time I launched the game, there was a wonderful feeling of warmness while i was exploring it's world and - it was awesome!

Witcher 3 didn't do it for you? It was the most "you are actually here" game since Morrowind, which I agree, somehow got the feel just perfect.

Gotta figure that's why people are still modding Morrowind. It's not for the graphics or the combat engine XD

I love with these games those experiences you feel are unique to you. For example:-
Fallout 3. I just left the Vault at the beginning of the game and travelled west. A dust storm brewed up and suddenly out of it emerged a travelling trader!
It amazed me.

Actually no. 1st thing I do in Fallout (1,2,3,nv) is to completely turn the music off. I am not used to run around with mp3 attached IRL.

Haven't played Morrowind, but did complete Skyrim. Good game.

Coincidentally I read about voice acting in Skywind (Morrowind as Skyrim mod) on a Dutch tech site.

The Dutch page links to https://tesrenewal.com/blog/blog-post-september-2015
FAQ: https://tesrenewal.com/skywind-faq
Apparently they're also working on an Oblivion mod for Skyrim called Skyblivion.

Good non cartoon graphics help make the game more immersive.

I am waiting for final version of Skywind mod.

Back in the day, I got a similar impression from Operation: Flashpoint.

Yeah, because what Morrowind really needed was quest compass and dumbed down character system...

To be honest I haven't started TES series yet (except Arena and Daggerfall) so can't tell difference between their gameplay.

Well, in that case, just play Morrowind with the Overhaul mod, don't bother with Skywind.